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Omega General Help / cold start issue and fuel trim error
« on: 07 January 2019, 14:28:30 »
Hi...on my 2002 2.6 V6 omega it takes a long crank over to start engine from cold (5sec or more, when it has finally fired up, it is vey lumpy for a further 5 secs untill fuel (i guess) normalises pressure.
Yesterday and this morning when engine caught and settled after 10 sec i turned engine off and re cranked engine immediately. All ok, no problems started as if all is normal, repeted this a further 5 times, never missed a beat started fine with no lumpyness in the first 10sec or so of being fired up. What i have changed recently 4 weeks ago, 6 bosch plugs, delphi coil packs, fuel filter, GM fuel pressure regulator and GM temperature sensor all to no avail. Could it be an issue with the fuel pump or possible air leaks. The garage i go to did a fuel pressure test and noted when engine was switched off the pressure dropped. The garage is running another check on this today. Is it normal for pressure to drop after switching engine off?? As for everthing else, all runs very well, after the initial difficult cold engine start the car is perfect for the rest of the day until the next following morning. Forgot to mention the fuel trim error is present. Any help or suggestions greatly received. dunc52
Yesterday and this morning when engine caught and settled after 10 sec i turned engine off and re cranked engine immediately. All ok, no problems started as if all is normal, repeted this a further 5 times, never missed a beat started fine with no lumpyness in the first 10sec or so of being fired up. What i have changed recently 4 weeks ago, 6 bosch plugs, delphi coil packs, fuel filter, GM fuel pressure regulator and GM temperature sensor all to no avail. Could it be an issue with the fuel pump or possible air leaks. The garage i go to did a fuel pressure test and noted when engine was switched off the pressure dropped. The garage is running another check on this today. Is it normal for pressure to drop after switching engine off?? As for everthing else, all runs very well, after the initial difficult cold engine start the car is perfect for the rest of the day until the next following morning. Forgot to mention the fuel trim error is present. Any help or suggestions greatly received. dunc52